System and apparatus for facsimile telegraphy



l w}, 30, 1943, R j 155 ET AL 2,31 I

SYSTEM AND APPARATUS FOR FACSIMILE TELEGR/CPHY Filed Sept. 2, 1939 9 Sheets-Sheet 1 INVENTORS R.J.WISE L..G. STEWART BY R. D. PARROTT Mamh 30, 1943. w ET AL 2,315,361

SYSTEM AND APPARATUS FOR FACSIMILE TELEGRAPH! Filed Sept. 2, 1959 9 Sheets-Sheet 2 FIG. 2

INVENTQRS R. J. w: SE

- 1.. c STEWART 7 BY R. D. PAR ROTT March 30, 1943. J 155 ET AL 2,315,361

SYSTEM AND APPARATUS FOR FACSIMILE TELEGRAPHY Filed Sept. 2, 1939 9 Sheets-Sheet 3 March 30, 1943. R. J. WISE ET AL 3 3 SYSTEM AND APPARATUS FOR FACSIMILE TELEGRAPHY Filed Sept. 2, 1959 9 sheets-sheet 4 FIG. 4

INVENTORS R.J.W|SE 1.. G. STEWART,

BY R. D. PARROTT J I ORNEY 7 March 30, 1943. J 155 r- I 2,315,361

I SYSTEM AND APPARATUS FOR FACSIMILE TELEGRAPHY Filed Sept. 2, 1939 I 9 Sheets-Sheet 5 N INVENTORS I I 1 v y f A I R.J.WISE 79/ 97/ 3 BY L. c. STEWART R. D. PARRETTCW h ATFORNEY March 30, 1943. R, W155 ETAL 2,315,361 7 v SYSTEM ND APPARATUS FOR FACSIIILE TELEGRAPH! Filed Sept. 2, 1939 9' Sheets-Sheet e FIG-.9

-10 I INVENTORS R.J.WISE I BY L.G. STEWART R. D PARR TT- March 30, -R; J; w jsE ETAL YswEm AND APPARATUS FOR FACSIMILE TELEGRAPHY,

Filed Sept. 2, 1939 I 9 Sheets-Sheet '7 CHOPPER MOTOR DMVWG MOTOR ENVENTORS RJVHSE LIASTEWART RmlpARapTT WMLWJ. (15 W i C4? 1 AT RNEY Z March 30, 1943.

R. J. WISE E AL I 7 2,315,361

SYSTEM AND APPARATUS FOR FACSIMILE TELEGHAPHY Filed Sept. 2, 1959 9 Sheets-Sheet a FIG. I3

INVENTORS R.J.WI'SE1 1.. G.STEWART BY VR.D.PARR

o T y A ORNEY' March 30, 1943; w s g ET AL 2,315,361

I :SYSTEM AND APPARATUS 'FOR FAcsIMILE TELEGRAPHY Filed Sept. 2; 1939- A 9 Sheets-Sheet 9 CHOPPER MOTOR 2 I45 N BY R..D. PARROTT 1 I 7 ATTO EY l73 lmsul Patented Mar. 30, 1943 SYSTEM AND APPARATUS FOR FACSIMILE TELEGRAPHY Raleigh J. Wise, Dunelleu, Louis G. Stewart,

Rutherford, and Robert D. Parrott, West New York, N. J., assignors to The Western Union Telegraph Company, New York, N. Y a corporation of New York Application September 2, 1939, Serial No. 293,188

30 Claims.

The present invention relates to telegraphy, and more particularly to novel systems and apparatus for communication by the transmission of pictures, messages and other subject matter in facsimile. I

The primary object of the'present invention is to provide a novel combined facsimile transmitter and receiver which may be operated by an inexperienced person and which therefore makes it available for personal use by a patron of a commercial telegraph service or other members of the general public.

Another object of the invention is to provide a novel system for facsimile intercommunication with a central office of a telegraph company.

In accordance with the present invention, pictures, messages or other subject matter are transmitted from and received by a compact com-' bined sender and receiver which operates appropriate signals at the central oflice with which communication is desired, but which, in the preferred system, is under the direct control of the operator. The simplicity of the apparatus and refinements of design embodied therein permit it to be operated by an inexperienced person without direct control being exercised from the central office during the transmission period. Likewise when the machine is used as a receiver, it is under control of an inexperienced operator, but is stopped automatically following the reception of a message.

A further object of this invention, therefore, is to provide novel facsimile apparatus having means for signalling a central office when facsimile communication therewith is desired.

A still further object of the invention is to provide a novel facsimile communication system affording means to signal a subscriber froma central ofllce when communication is desired.

A still further object-of the present invention is to provide facsimile telegraph apparatus embodying novel control means Still another object of the present invention resides in the provision of novel means for driving and advancing a copy holder for cooperation with a pickup or recording device.

Still another object of the invention is to provide a novel facsimile telegraph system having several stations which may transmit messages in facsimile to a telegraph central office or re- In the drawings:

Fig. 1 1s a view in perspective of a combined facsimile transmitter and receiver embodying the invention in its preferred form;

Fig. 2 is a front elevational view of the machine of Fig. 1 with the cover removed;

Fig. 3 is a view in plan with certain of the parts removed for the sake of clearness of illustration;

Fig. 4 is an enlarged fragmentary horizontal sectional view taken on line 44 of Fig. 2;

Fig. 5 is an enlarged fragmentary vertical sec- I tional view taken on line 5-5 of Fig. 3;

Fig. 6 is an enlarged fragmentary vertical sectional view taken on line 6-6 of Fig. 3;

Fig. 7 is a view similar to Fig. 6, a section being taken from the left side of Fig. 4 as indicated by the arrows on line 1-1 of Fig. 4;

Fig. 8 is an enlarged fragmentary sectional view5of the copyholder taken on line 8-4. of Fig.

Figs. 9 and 10 are sectional views illustrating details of the optical scanning device;

Fig. 11 is a view in front elevation of a modification of the machine illustrated in Fig. 1;

Fig. 12 is a diagrammatic showing of the electrical features of a control system in accordance with the invention;

Fig. 13 is a diagrammatic showing of theelectrical features of terminal transmitting and recording equipment suited for use in a system of Figs. 12 and 14; and

Fig. 14 is similar to Fig. 12 and illustrates electrical features of a modified system.

Referring to the drawings and for the present to Figs. 1 to 10 thereof, a combined transmitting and recording machine, indicated generally by the reference numeral 9, comprises a base or frame ill, a removable cover I! and a copyholder l2. As shown more clearly in Fig. 2 of the drawings the copyholder I2, in the form of a cylinder or drum, is journaled for rotation upon a shaft 14, the latter being rotatably mounted in brackets l6 and I1 upstanding from the base In. A motor 18, which is adapted for synchronized operation with a remote transmitter or receiver, imparts driving power to the shaft H by way of the worm l9 and the worm wheel 2| secured to the shaft. A lead screw 22 for advancing the cylinder I2 is journaled in brackets I1 and 24 and it is driven by a pinion 26 on the shaft i4, meshing with a gear 21 secured to the lead screw shaft.

Details of the structure of the copyholder I! are illustrated by Fig. 8 which is seen to comon the copyholder. -A spring garter 39 also as-- sists in keeping the sheet 38 in position on the cylinder. The cylinder I2 is constrained to rotate with the shaft H by means of 8 Pin 49 which engages the rod member 34 as shown in Figs. and S-While permitting the copyholder l2 to be freely rotated on the shaft |4 through an angle of approximately 180.

Longitudinal scanning movement is imparted to the cylinder I: from the lead screw 22 by means of a half nut member 4| which is carried adjacent the end of a member 42, the latter being journaled upon a boss 43 projecting from the end plate member 3| of the copyholder l2. During rotation of the copyholder |2, the half nut 4| is pressed into meshing engagement with the lead screw 22, unless it is restrained by the bail 49 and its associated mechanism later to be described; by means of friction discs 49 and 41 (Fig. 8). These discs are pressed against the sides of the member 42 and the disc 46 is pressed into engagement with the end wall of the cover member 3| by means of a garter spring 4! encircling the conical end '49 of a collar "which is secured to the boss 4: by a set crew 5:. With the arrangement described, as the cylinder |2 rotates in the direction of' the arrow as indicated in Fig. 6 the half nut member 4| will be retained in meshing engagement with the lead screw 22 so as to advance the-cylinder toward the left as viewed in Fig. 2 of the drawings.

Referring now to Figs. 6 and 'l the bail member 45, previously referred to, has its inturned arms 53 pivotally mounted upon the upstanding bracket 24 and a bracket 54 (Fig. 4). The mem ber 42 is notched as indicated at 55 to receive the bail member which is pressed upwardly during normal operation of the machine against the horizontally extending portion 59 of the member 42 by means of the armature 51 of an electromagnet structure 58, which includes a biasing spring 59 tending to move its armature upwardly. When the cylinder I2 is rotated manually in a clockwise direction as viewed in Figs. 5 and 6 of the drawings, after the motor l8 has stopped, the member 42 travels therewith, due to friction members 49 and d1, until the upwardly biased bail member 45 enters the notch 55. This prevents the reengagemerit of the half nut 4! with the lead screw until the magnet 58 is energized. This position of the parts is shown in Fig. 7 of the drawings. Fig. 6 shows the position of the parts during scanning. Control of the motor l8 and operation of the magnet 58 will be described hereinafter in connection with the description of Figs. 12, 13 and 14 of the drawings. The bail member 45 is cut away or notched at 60 adjacent the unthreaded part of the lead screw shaft 22 so as to insure complete disengagement of the halfnut before the cylinder is returned to the right. If movement of the cylinder I2 is attempted without rotating it to disengage the halfnut 4| from the lead screw 22, the edge of the notch or depression 60, nearer the right hand side of the machine as viewed on Fig. 2, is abutted by the portion of the member 42 adjacent its edge 56. Upon rotation of the cylinder to disengage the halfnut from the lead screw,

the parts 42 and 45 assume the position illustrated by Fig. 7 of the drawings and the cylinder may be returned to its starting position at the right.

Longitudinal movement of the cylinder |2 from its starting position at the right of Fig. l is prevented by a spring 92 (Figs. 2, 6 and 7) having an upturned end 83, which because of its flexibility permits the cylinder |2 to be moved to the right with the half nut disengaged, but prevents its movement to the left. The upturned end of the spring member 03 can be cleared by the end of the member 42 in preparation for movement to the left only when the magnet 59 is energized to withdraw the bail member 49 from the notch 55. The spring 69 is conveniently mounted on bracket 9|. 1

A double throw switch ll (Figs. 2 to 4) which is of the type biased to a normal position, is supported upon a bracket 99 so that its operating member 91 is aligned for engagement with the end of a switch operating rod 69 which is slidably mounted in a bracket 99 and a. bracket member 1| (Fig. 4). The switch operatlngrod II is biased for movement toward the left by means of a spring 12 encircling the rod and bearing against bracket 89 and adjustable collar 18. A handle 11, formed at the end of the rod opposite the switch 9!, is conveniently accessible to an operator, the casing being recessed as shown at ll (Fig. 1) to permit access to the cylinder I: in its initial position and the handle. A spring 19 (Fig. 2), extending from the bracket 69, is provided to retain the rod 69. out of engagement with the switch operator l1 and is formed for engagement with a collar 9| adjustably secured to the rod by a set screw 92 (Fig. 4). The spring 19 is bent downwardly at its free end so that when the collar II has been drawn toward the right as viewed in Fig. 2 past the hump 92 on the spring the strength of the spring 13 is insufficient to return the rod to the left. the left into engagement with the switch operator 97 when the half-nut carrying member 42 is adjacent the end of its travel by engagement thereof with the top portion 95 of a stop member 99 adjustably secured to the rod 69 by a set screw 81. This stops operation of the machine at the end of a complete scanning movement of the drum |2. Unnecessary and unwanted rotation of the rod 68 is prevented by engagement of a notch in the member II with a flat member 99 secured to the support II which also holds the spring 63.

Pictures, messages, or other subject matter may be recorded on the sheet II, which in this instance will be a suitable record blank, by a stylus 9| mounted at the end of a stylus carrying arm 92 (Fig. 5) which is in turn carried by a member 93. The latter is secured for. angular adjustment by a set screw 94 upon a rock shaft 96. The rock shaft just mentioned is journaled in the previously described bracket 24 and a bracket 91 as shown in Fig. 4 of the drawings. When a record is to be made on the sheet 39, a stylus operating magnet indicated by thereference character 99 is energized as will be explained in connection with the description of Figs. 12 and 14 of the drawings. The armature of this magnet is pivoted at I02 and is connected by a link I93 to a member I04 adjustably secured on the shaft 96 by means of a set screw I05. When the magnet 99 is energized the shaft 96 is rocked to bring the stylus 9| into contact with the record sheet. The

handle 11 has an upturned end I96 which rolls The rod 99 is moved to the spring garter 30 along the cylinder as it advances to keep the spring garter clear of the scanning devices.

When the machine is to be usedas a transmitter, the sheet 38 will display the picture or message to be transmitted whichwill be scanned by the photoelectric pick-up device (Fig. 3) comprising the lampll, the lens tubes I08 and I08,

j I turned to its "send" position.

the photocell H0 and the light chopper ill. The

lamp I01 is adiustably mounted upon a post II4 (see also Fig. 9) carried by the base II, adjustment being accomplished by a set screw II! which allows for rotation of the bracket I I6 about the post H4 and a set screw and lock nut combination III and II! which permits the lampto be rotated around its own axis. An apertured shield I II allows light flux from the lamp to pass through the tube I08 ,where it is focused upon the surface of the sheet 38. The lens tube I09 ends in an"apertured wall I2| (Fig. 10) upon which is. projected an image of the illuminated area of the sheet 38. Light from a small portion of this image passes through the aperture I28 and through the spaced slots in the light choppe'r III to the photocell III. The light chopper disc III is supported on the rotor shaft I24 of the light chopper motor I28 and serves in a well known manner to cause the photocell I I0 to generate a carrier frequency. It will be undertsood however that the carrier frequency may be gen-- erated separately and be modulated by the varying current produced in the photocell H0 as the subject matter'on the sheet 38 is scanned.

An upstanding instrument panel I28 of channel shape (Fig. 2), the open side of which extends to the rear and has mounted therein a filter .or an air purifying member I29 of an appropriate type, is mounted adjacent the rear edge of the base I0 by screw threaded means engaged in holes Ill appearing in Fig. 3. Fumes or gases, which may be evolved during recording in the neighborhood of the stylus 9|, are forced through a conduit member I 33 by means of a central oilice' in a manner to be described, the

electromagnet 58 will be energized to draw the member 4! from the notch 88 (Fig. -6) allowing the half nut member 4| to engage the lead screw 22 against which it is pressed by action of the friction discs 48 and 41 in the manner already explained in detail. When the surface or the sheet bearing the message to be transmitted has been scanned by axial movement of the cylinder I2, the lower end of the member 42, which travels along with the cylinder, engages the member 88 forcing the rod 68 to the left to operate the switch 85, thereby stopping the machine.

When desired the cylinder I2 may be restored to its initial position by rotating it manually in a. clockwise direction to disengage the half nut GI from the lead screw 24. As previously exv plained, the notch 60 on the bail 45 compels the operator to completely disengage the half nut before the cylinder can be returned. It will be undertsood that the bail may be provided with several spaced notches when transmission of sev- 'eral standard lengths of messages is contemplated. When the cylinder I2 is returned as far as it will go to the right, the position of the bail 45 in the notch 55 prevents manual engagement of the half nut and the spring 63 prevents inadvertent movement of the cylinder I2 toward the left.

fan I24 on the rotor shaft ofthe motor I8 to the chamber formed in the rear of the channel shaped instrument panel I28 and the deleterious matter is removed and retained in the filter I20. The inwardly facing side of the instrument panel I20 affords a convenient mounting surface for the apparatus comprising the amplifiers and other-electrical equipment of the machine. 1

In operation of the mechanical parts of the apparatus thus far described as a transmitter, a person wishing to transmit a picture or mes sage in facsimile writes or otherwise impresses the message on the surface of the sheet 38. Where the machine 9 is to be used for a .commercial service, the message sheet 38 is generally provided with the printed matter thereon indicated by the reference character I33 '(Fig. 1) and the message is to be written beneath this printed matter. To insure that the message will be recorded at the receiver in its proper position on the receiving sheet or blank, the sheet displaying the matter to be transmitted is wrapped The mode of operation of machine 9, when used as a recorder, is similar to that already described except that the'send-receive switch is placed in the receive position which'conditions the control circuits of the machine in a manner to be described so that the magnet 99 will be energized with the magnet 58 to movethe stylus 9| into engagement with a recording blank retained in position on the drum I2 by the garter spring 38.

Referring to Fig. 12 of the drawings, diagram-.

maticallyshowing electrical features of the machine 9 and the central oiiice sending and reswitch I42 is diagrammatically shown as comaround the cylinder I2 in such a way that one amplifier RA. It will be understood that there I are as many active jacks as there are machines 9 in service and that these jacks and their associated signals are preferably grouped together. The communication circuit L is bridged by inductances I49 and I5I at the central oflice and the transmitter receiver 9 respectively. The midpoint of the inductance I5I is connected through the coil of the polar relay I52 and the resistance I53 to a brush I54 (Figs. 2 and 12) which bears on a conducting disc I56 rotatable with the shaft I4. The conducting disc I56, which is grounded through the machine parts, is provided with an insulating portion I51 which is correctly placed angularly with respect to the line I99 inscribed on the cylinder I2.

The midpoint of the inductance I49 at the central c-fiice is connected through relay coils I56 and I59 to a source of negative potential via the contact springs I6I of aha jack I41. The relay I59 is of the usual type whereas the relay I59 is adjusted so that its contact tongue will move only when it is energized by current of a strength great r than that necessary to operate the relay I58. The tongue of the relay I59 is connected to a suitable source of potential and lights a lamp I62 from its front contact when it is energized. The tongue of the relay I56 is connected to the back contact of the relay I59 and its back contact is connected to a lamp I69. The resistance I52, which is included in what may be called a simplex-circuit" utilizing both sides of the line L and derived from the midpoints of the inductances I49 and I5I, is bridged via one of the switch blades I46 by the tongue and front contact of a relay I66, the operating coil of which is connected to the plate supply conductor I61 for the amplifier RA which is fed from the rectifier I69.

When it is desired to transmit a message to the central station from the machine 9, the send-receive switch I42 is moved to its send position, which it occupies in Fig. 12 of the drawings, and the start-stop switch 65 is closed to energize the motors I6 and I26 as previously explained. The driving motor I8 turns the cylinder I2, but the cylinder does not feed due to the half-nut 4I being disengaged by the half-nut engaging bail 45. The lamp I01 is lighted, the chopper motor 126 starts and the amplifiers TA and RA are energized. As the current from the rectifier I68 through the relay I66 approaches its maximum value, this relay is operated, shortcircuiting the resistor I53 in the simplex-circuit and lifting the ground off that circuit which was applied through its back contact via the conductor I69. The resulting increase in current through the simplex-circuit operates the relay I59 at the central office lighting the lamp I62. A receiver I1I, indicated diagrammatically on Fig. 12 and more in detail by Fig. 13, at the central oiTlce, which isv associated with the plug I12, is connected'to the line L by placing the plug I12 in the jack I41 connected to the calling machine and the simplex-circuit is extended through the coil of relay I13 and contacts of relay I11 to .negative potential. The relay I1! is adjusted similar to the relay I59 to operate upon the higher values of current in the simplex circuit and this relay pulls up and operates a slow-to-release relay I14, which removes a locking circuit over the conductor I 16 from the coil of a relay I11, making this last named relay responsive to the next operation of relay I19 by the establishment of a temporary locking circuit over conductor I16 and to make contact of relay I19. When the simplex circuit is interrupted at the phasing contact I56 of the send-receive machine 9, the relay I19 releases, releasing the relay I11, which looks itself out through one of its break contacts and the make contact of relay I14 and operates the phasing magnet I16 and the half-nut and stylus magnet I19 of the recorder I1I over the conductor I66 (Figs. 12 and 13). The relay I11 also reverses the polarity of battery in the simplex circuit to positive, operating the polar relay I52 previously described in the send-receive machine 9, which in turn closes the circuit including the half-nut engaging magnet 59, thus allowing the half-nut to drop into the feed screw to start feeding of the cylinder I2 toward the left so that it is scanned by the light I01.

As the message on the sheet 96 is scanned, the current set up in the photocell III is passed through the transmitting amplifier TA over the line L to the recording amplifier RAI in the central oiiice from which it is fed through the signal inverter IN to the stylus I62 (Figs. 12 and 13) of the recorder Ill.

The signal inverter III is used since the copy transmitted from the photocell H6 is a negative copy. The copy received at the central oiiice upon the recorder I" is reversed in the inverting device I6I which comprises two vacuum tubes I64 and I66 heavily biased for class C operation by a negative biasing potential applied to the grids from the source I61. The plates of the tubes Joined in parallel are connected directly to the stylus I82 and are also connected through a resistance I96 to a source of relatively high potential I69. When a heavy signal is fed into the circuit a heavy plate current flows from the source I89 through the resistor I86 of such magnitude that the resultant voltage is not suflicient to produce a mark on the recording paper "I on the recording drum 192. When no signal is fed to the circuit, no current is drawn through the tubes and the total voltage from the source I99 is applied to the stylus I92 thus causing it I to record a mark. The fluctuations in the level of the incoming signal control the amount of voltage available for marking purposes thus exactly reproducing the received signals at the stylus except that the maximum and minimum values of the signals are reversed.

As the cylinder I2 of the machine 9 moves from right to left it eventually operates the start-stop switch 65 as previously explained placing it in the stop position. The current value in the simplex circuit and therefore in the conductor I14 returns to its normal value which causes the relay I19 to release. This releases the relay I14 which takes the lookout circuit from the relay I11 and operates this relay, initiating a signal which is transmitted over the conductor I54 (Figs 12 and 13) to.operate the relay I96 (Fig. 13) which controls the drum changing mechanism of the recorder "I. The polarity of the current source to the simplex circuit is also reversed. The plug I12 of the recorder is then pulled down from the Jack I41.

The mechanical arrangement of recorder IN is similar to that disclosed in the application of G. H. Ridings, et al., Ser. No. 264,512, filed March 28, 1939, now Patent No. 2.2553369, granted September 16, 1941, and the mechanism illustrated diagrammatically on Fig. 13 of the drawings will now be briefly described for the sake of completeness. The cylinder I92 of the recorder I is interchangeable with like cylinders and is provided with arbors "land In which are supported for rotation by means of spindles I99 and "I provided with conical ends for engaging indentations in the ends of the arbors on the drum.

The spindle I99 rotates the drum I92 by means ofa driving connection comprising a pivoted arm 292 attached to the spindle I99 and urged by 4 s the cradle and is picked up upon the next succeeding inward movement of the rod 2", following which the circuit of the motor 2341s intermeans of a spring 292 secured to the spindle and the arm against a stop pin 204 extending radially from the spindle. The movable end of the am 202 engages a pin 294 formed on the arbor I91.

A friction clutch 291 serves to connect the spindle The stylus supporting carriage 2i] is slidably mounted on rails 2 along which it may be prorupted by the relay ,I9E which is controlled by a pair of contacts 249 operated by a cam "I.

when the machine 9 is used to receive a message from the central oiilce over the line L, the

plu 252 is inserted in the lack I41 of the machineto be called which extends the simplex'cir cuit over the conductor 253 through the coil of the" relay 294 to a source of positive potential which operates'the polar relay I92 in the remote send-receive machine 9 to sound the buzzer or other suitable signal 2 59. The machine of Fig. 13 may serve as a transmitter as previously described in which case the photocell 222 on the scanning carriage thereof'is connected by a transthe lack I41, the line L, the transmit-receive pelled by a feed screw 2I9 and a half nut 22I.

The feed screw 2I9 is driven by the motor 299 through an appropriate gear in the reduction gearing 2| I. A retractile spring 223 is attached to the carriage 2" and to any convenient stationary member so that when the half nut 22I is disengaged from the feed screw, the carriage will be returned to an initial scanning point at the left as viewed in the drawing. It will be understood that the carriage 2II is also provided with a scanning light (not shown), a photocell 223 (Fig. 12) and a system of lenses (not shown) by which optical scanning of subject matter for transmission to the machine 9 appearing on a sheet, similar to the recording sheet I9I, may be effected.

The shaft I99 is provided with a notched disc 224adapted for engagement with the pivoted latch member 229 which is urged into latching of the notch in the disc 224 is so located with respect to the lap in the sheet "I that when the position by thespring 221. The angular position disc is released the stylus I22 is at the beginning of a scanning line on the sheet.

In order to release one cylinder I92 and engage another for rotation, the rod 2 is provided with a pin 228 which is positioned In the path ofthe vertical arm of a bell crank 229 pivoted on the bracket 2I4 as shown.

The cam, follower 22I cooperates with a cam 292 which is secured on a shaft 233 driven from the motor 234 by a worm wheel 239. As the cam 232 is'rotated, the horizontal arm or the bell crank 229 is raised-there by moving the shaft 2M to the left against theaction of the spring. 2 I9. The cylinder drops and is received on a cradle formed by a pair of spaced upright members 291 and 238 which are secured to a rock shaft 239 oscillated by cam 2 and cam follower 242. The cams 232 and 2 are-secured to the shaft 233 in such angularrelationship that a tilting of the cradle follows axial movement of the shaft 2!".

Fresh cylinders are contained in a magazine.

new cylinder falls by gravity into the notches of mitting ampliflerTAl to the plug 2l2through switch I42 in the receive position to the receiving amplifier RA. Picture reversal, to obtain a D081? tive copy at the machine 9, may be accomplished I by using an additional photocell 259. as disclosed in Patent No..2,158,391 to R. J. Wise. Conductors 291 and 2i'l correspond in function to conductors I99 and I94 respectively and areconnected thereto. If desired, a separate machine similar to III may be used equipped with the photocells 229 and 255 in which case, the conductors 291 and 251' will be connected to this separate machine. The operator at the transmit-receive machine 9 places a. receiving blankvon the cylinder and moves the transmit-receive switch I42 to the receive position and operates the start-stop switch 99 to the start position, The buzzer circuit is interrupted and the amplifier RA heats up causing the relay I98 to operate. The resistance I93 in the simplex circuit isnot shunted in this case, being open at the transmit-receive switch, and the value of current in the simplex circuit remains low. A gain control 299 (Fig. 1) in the amplifier RA allows the operator to adiust the machine for best results when working as a receiver. The relay 294 of the transmitter bank of relays is adjusted to operate on this low value of current, and the slow-to-release relay 299 and relay 259 and their associated circuits will be responsive to the phasing pulse from the transmitter in the same manner as previously described in connection with relays IIl, I14 and I 11. The low current relay I58 associated. with the line L follows the phasing pulse giving a flicker on the receiving lamp I63 indicating that the remote machine is in proper of the machine 9 with the switch I42 in the 111-? correct position for the operation desired, and a signal lamp 263 which indicates misplacement of the switch I42 by illuminating the transparent or translucent member 264 shown in Fig. 1. The parts which are identical with those illustrated in Fig. 12 are designated by the same reference characters on Fig. 14. In Fig. 14 the relay.268 is similar to the relay I69 in Fig. 12 but the operating circuits thereof are modified in a manner which will presently appear.

The operating coil of the relay 262 is connected in series with start contact of the start stop switch 65 and the contact tongue of the polar relay I52. The latter is in the idle position shown in Fig. 14, when no messages are being transmitted or received, because of the negative battery applied to the mid-point of the high current relay 268 at the central office. When a message is to be sent from the machine 9, switch 65 is placed on its start contact and relay 282 is energized and looked through its contact tongue 269. This prevents the relay from releasing when the polarity of the simplex circuit is reversed as explained in connection with Fig. 12. The relay contact tongue 2'" short circuits the resistance I52 to operate the calling relay 2" at the central ofllce.

The tongue 212 of the relay 2 removes the direct ground from the simplex line making effective the ground applied through the disc I" and the brush 4. The tongue 21! oi the same relay connects the half-nutmsgnet II in circuit with the polar relay I52 so that the half nut magnet will be operated in response to operation of the polar relay in the manner explained in connection with Fig. 12 oi the drawings.

The relay 262 is not operated when the machine 9 is used as a receiver since the polar relay is reversed to operate the buzzer 256 from the central ofllce prior to movement of the switch BI to its start position and does not resume its idle position until reception of the message by the machine 9 is complete. Resumption of the idle position by the polar relay operates the lamp 282 as a signal in a manner to be described. The half-nut magnet 52 is operated for reception upon operation of the relay 2".

The lamp 262 is connected in series with the filament of the rectifier tube I" and may be short-circuited over the conductors 2" and 2" ii the switch I42 is in its correct position for transmission or reception respectivelyin the following manner. When the machine I is being used as a transmitter the contact tongue 21! of the relay 262 and its front contact are included in this short-circuiting path. When the machine 9 is operated as a receiver, the contact tongue 21! woperates with a back contact to close the short-'circulting path around the lamp 2".

The relay 2'2 functions to prevent transmission with the switch I42 in the receive position in the following manner. The relay 202 is operated from the start-stop switch 64 when the latter is moved to start position, but only if the tongue of the polar relay I52 occupies the idle position shown in Fig. 14. With the start-stop switch 55 in start position and the switch I42 in the proper transmit position, the indicator lamp 263 in the filament circuit of the rectiner tube I68 is short-circuited through the transmit receive switch I42. It the transmit receive switch is incorrectly placed in the receive position when sending is desired, the resistance 01' the lamp 282 is sumcient to prevent the rectifier tube from heating up to the point where the relay 268 will operate. The short circuit path previously described around the lamp 2" is open at the switch I42, which, as-pointed out above, maintains the lamp in operation and indicates that the switch is in the wrong position.

If the transmit receive switch I42 is in the send position when a message is to be received in response to a call from the central ofllce, operation oi the relay to engage the half-nut lighted and prevents the rectifier from supplying plate current to the amplifier. The shortcircult path around the lamp including the tongue 211 of the deenergized relay 202 is open under N is prevented since the lamp 2 Ema l these conditions at the switch I42.

Thus a person inadvertently trying to send or receive with the transmit receive switch in the telegram Just received-is desired. Otherwise the a machine will be automatically stopped when the cylinder I2 moves all the way to the left.

The central oillce equipment shown at the left of Fig. 14 is slightly diiferent from that disclosed in Fig. 12. Two jacks 21s and "I are employed for transmitting and receiving respectively to accommodate the sending plug 222 and the receiving plug 283. These two jacks for a single machine 8 are provided to make it possible for the operator at the main ofllce to exercise control over the power received from the sendreceive machine I by means or a pad 244 without introducing a loss in the line which would also affect transmission to the send-receive machine from the central office. The same type 0! recorder and transmitter shown In Fig. 13 may be used with the apparatus in Fig. 14 and the receiving relays I12, I14 and I" are the same as described previously. Connection to the recorder l and transmitter is established over conductors Ill and I24. Also transmitting relays 224, 2"

and 2" are the same as the Identical transmitting relays described in connection. with Fig. 12 of the drawings.

. The calling arrangement in the central since as shown in Fig. 14 for the modified apparatus comprises the previously described relay 2" which lights the calling signal lamp '2" when the start-stop switch I! is placed in the start position. This lamp is extinguished when the plug 242 is inserted in the Jack 2".

The coil of the relay 2" corresponds in function to the Inductance I42 01 Fig. 12. However, when the-plug'2l2 is inserted in the jack 2", the inductance 2 terminates the simplex circuit formerly terminated at the mid-point of the winding of the relay 2". An inductance 241 terminates the simplex circuit when the receivmg jack 2" Is in use.

It is believed that operation 0! the apparatus of Fig. 14 in conjunction with the machine of Fig. 13 for transmission to and from machine 8 will be obvious from the foregoing in view 02 the previous description of the operation of the apparatus of Fig. 12 in conjunction with'the machine of Fig. 13.

Figs, 12, 13 and 14 disclose systems ior esiablishing communication with a central oilce from a plurality of machines I terminating in Jacksat the central office. However, the machine 9 or the present invention is especially adapted for use as a subscriber's substation machine in the concentrator system disclosed and claimed in the copendlng application oi. Blanton message for sending at any time.

et al., Ser 'No. 298,872, filed Patent No. 2,265,339. I

Fig. 11 of the drawings shows a modified form of Fig. 1 which is provided with an extended cylinder 289 of ample length to accommodate two messagesheets, one of which may be a sheet 29i containing a message for transmission, and the other in the. form of a suitable blank 292 adapted to be marked by the stylus 293, the lat- Oct, 11, 1939, now

ter being similar to the stylus previously described and mounted upon a shaft 294 corresponding to the shaft 96 of Figsll to ,10. I With the elongated cylinder 28!, a message may be received at any time since it will not be neces sary'to remove the blank 292 until the message has been recorded thereon inasmuch as space on the cylinder is available to accommodate 8. Both of the sheets 2!! and 292 are retained in position by garter spring members 296 and 291 in the man ner previously described and in addition the flanges 29! and 29lare recessed in a manner similar to that illustrated in Fig. 8 of the drawings; I

From theforegoing complete description of two illustrative embodiments of the invention port said copyholder, means to rotate said member during a scanning operation, a lead screw, a recessed member designed to engage said lead screw upon rotation of said copyholder to ad'- vance the same axially upon said support, means to prevent engagement of said recessed member withsaid lead screw, and an electromagnetic device to operate said last named means whereby to permit said recessed member to engage said a lead screw.

5. Facsimile scanning mechanism comprising a rotatable drum to support a member to be scanned, a shaft extending axially through said drum to rotatably and sidably support the same, a lead screw spacedfrom said shaft, a member projecting radially fromsaid drum and rotatably supported thereon, friction means interposed between said radially extending member and said drum tending to drive said member, a member having a threaded recess on said radial member to engage said lead screw, and means operand their operation, it willbe seen that a telegraph system for providing transmission to or from a customer's office and operable by inexperienced persons is provided by the present invention. The invention also provides facsimile machines which, because of the inventive features thereof, can be operated interchangeably as transmitters or receivers by unskilled persons. -While this invention has been explained in detail in connection with several embodiments thereof, it is to. be understood that the invention may be embodied in other forms and, therefore, the invention is not limited except as indicated by the terms and scopeof the appended claims.

What is claimed is:

l. Facsimile scanning mechanism comprising a rotatable cylinder to support a member to be scanned, means to slidably support said cylinder and impart rotation thereto, a lead screw, 3.

member rotatably supported by said cylinder and extending therefrom, and means to bring said cylinder supported member into operative engagement with said lead screw. I

' 2. In facsimile apparatus, a rotatable copyholder and a stationary scanning device,,a rotatable support upon which said copyholder is slidably mounted, means to rotate said support, and means to impart scanning movement to said copyholder comprising a screw threaded member and a member having frictional engagement able inresponse to a-start signal to permit engagement of said recess'with said lead screw.

6. Facsimile scanning mechanism comprising a rotatable drum to support a member to be scanned, a shaft extending axially through said drum to rotatably and slidably support the same,

means to advance said drum longitudinally of said shaft during a scanning operation, and

means designed to cooperate with said drum advancing means and being frictionally coupled to said drum.

'7. Facsimile scanning mechanism comprising a copyholder, means to support said copyholder,

means to advance said copyholderalong said support for a scanning operation, a member for conventing means, and means to prevent axial movel I ment of said copyholder except upon operation of with said copyholder whereby to be biased for movement into contact with said screw threaded member, said screw threaded member being positioned to be engaged by said frictionally biased member.

3. In facsimile apparatus, a rotatable copyholder and a stationary scanning device, a rotatable support upon which said copyholder is slidably mounted, means to rotate said support, a lead screw spaced from said rotatable support, a member having frictional engagement with said copyholder and adapted to engage said lead screw when said copyholder rotates with said support, and means to permit said copyholder said engagement preventing means.

9; A facsimile scanning mechanism comprising a copyholder, a shaft to support said copyholder rotatably and slidably and to drive the same, a lead screw to advance said copyholder for a canning operation, a member having a threaded recess for connecting said lead screw with said copyholder, a member extending longitudinally of said copyholder to prevent engagement of said. first named member with said lead screw, and

signal controlled means to operate said longitu dinally extending member whereby to cause engagement of said first named member with said lead screw.

10. Facsimile scanning mechanism comprising a copyholder, a shaft to support said copyholder rotatably and'slidably and to drive {the same, a lead screw to advance said copyholder along said shaft forascanning operation, a member having to be rotated manually to disengage said momber from said lead screw. 7

4. A facsimile transmitter and receiver comprising a copyholder, a rotatable member to supa threaded recess for connecting said lead screw with said copyholder, a bail member extending longitudinally of said copyholder to prevent engagement of said first named member with said lead screw, signal controlled means to operate said bail member, and a flat spring member positioned in the path of movement of said first named member when it is disengaged from said lead screw to prevent longitudinal movement of said copyholder except upon operation of said ball member.

11. Facsimile scanning mechanism comprising a rotatable drum for supporting a member to be scanned, a shaft rotatably and slidably supporting said drum, a threaded shaft extending parallel with said first named shaft, a member rotatably mounted on said drum, a member having a threaded recess carried adjacent the free end of said rotatably mounted member and positioned thereon to engage said threaded shaft, a bail member extending longitudinally of said shaft and positioned in the path of swinging movement of said radially extending member, and electromagnetic means to move said ball member to permit engagement of said threaded member with said threaded shaft.

12. A telegraph system comprising a telegraph transmitting device, means to receive a message containing sheet for cooperation with said transmitting device, means to drive said message receiving means, means for initiatin movement of said drive means, and means operable in response to the operation of said movement initiating means when said device is in transmitting condition for signaling a remote receiving station to apprise an attendant at said receiving station that a message is awaiting transmission.

13. A telegraph system comprising a telegraph transmitting device, a copyholder for cooperation with said transmitting device, means to drive said copyholder, means for initiating movement of said drive means, means operable in response to the operation of said movement initiating means when said device is in transmitting condition for signaling a remote receiving station, and means at said receiving station to control the scanning operation of said copyholder.

l4. Facsimile scanning mechanism comprising a rotatable drum to support a member to be scanned, a shaft extending axially through said drum to slidably and rotatably support the same, a member secured to said drum in spaced relation to said shaft, and a radially projected member rigidly mounted on said shaft engageable with said drum member to cause said drum to rotate with said shaft.

15. Facsimile scanning mechanism comprising a rotatable drum to support a member to be scanned, a shaft extending axially through said drum to slidably and rotatably support the same, axially extending members in said drum spaced from said shaft and angularly spaced from each other about the axis of said drum, and a member projecting radially from said shaft to engage one of said angularly spaced members to cause said drum to rotate with said shaft.

16. A facsimile transmitter-receiver comprising an amplifier, a source of current for said amplifier, a relay in circuit with said current source, a signaling circuit including a serially connected resistance, an interrupter in said signaling circuit, and circuit connections to the contacts of said relay for short-circuiting said resistance to produce a rise of current in said signaling circut for signaling purposes.

1'7. A facsimile transmitter-receiver comprising a send-receive switch, mechanism in said transmitter-receiver operable upon connection to a power source, an amplifier for said transmitter-receiver, a power supply for said amplifier, a relay, connections between the contacts of said relay, said send-receive" switch and the power supply for said amplifier, said connections being established only when said "send-receive" switch is in the send position for transmission, and in the receive position for reception.

18. A facsimile transmitter-receiver comprising a send-receive switch, mechanism in said transmitter-receiver operable upon connection to a power source, a relay in circuit with said power source, an amplifier for said transmitter-receiver, a signal operated relay controlled from a remote station, the first named relay being connected through the contacts of said signal operated relay to permit operation of said amplifier only when said "send-receive switch and said first named relay are in correct position for the desired operation of said transmitter-receiver.

, 19. A facsimile transmitter-receiver comprising a send-receive switch, mechanism in said transmitter-receiver operable upon connection to a power source, a switch for connecting said mechanism to said power source, a relay in circuit with said switch, an amplifier for said transmitter-receiver, a signal operated polar relay controlled from a remote station, the first named relay being connected through the contacts of said signal operated polar relay to permit operation of said amplifier only when said "send-receive" switch is in the send position for transmission and the receive position for reception, and when said first named relay is energized for transmission and deenergized for reception.

20. In a facsimile telegraph system, a plurality of facsimile transmitters, a plurality of communication circuits, one foreach transmitter, a facsimile receiver having a movable-member,

means including one of said circuits to interconnect any one of said transmitters and said receiver for communication, a relay to control movement of said movable member, means rendered operative under the control of said one circuit upon the interconnection of one of said transmitters with said receiver to prepare said relay for exercising its control function, and means responsive to the operative condition of said transmitter in communication with said receiver for actuating said relay to initiate movement of said movable member of said receiver.

21. In a facsimile telegraph system, a plurality of facsimile transmitters, a facsimile receiver having a movable member, means to interconnect any one of said transmitters and said receiver for communication, means to control movement of said movable member, means associated with each of said transmitters and operable periodically for controlling the starting time of said receiver connected therewith, and means, responsive to one of the periodic operations of said controlling means associated with said transmitter in communication with said receiver, for initiating operation of said movement controlling means to cause movement of said movable member of said receiver.

22. In a facsimiletelegraph system, a plurality of facsimile transmitters, a facsimile receiver having a movable scanning member, communication circuits extending from said facsimile transmitters and terminating at a common point available for connection to said receiver, a relay to control scann ng movement of said member, a second relay operative upon interconnection 01 one of said transmitters with said receiver to prepare said first named relay for exercising its 7 2,315,361 control function, and a third relay, responsive to the operative condition of said transmitter in communication with said receiver, for actuating said first named relay to initiate operation of said receiver scanning member. I

23. In a telegraph system a plurality of stations, a central station, communication circuits to interconnect said first named stations with said central station, calling relays, one for each of said circuits at said central station, and means whereby each of said relays serves as a simplexed connection for the said circuit with which it is associated to provide communication with said first named stations over said simplexed circuits derived through said relays.

24. In a telegraph system a plurality of stations, 9. central station, communication circuits extending from said first named stations to said 27. In a facsimile machine, in combination, means to support a sheet tobe scanned, a scanning device, means to carry said sheet supporting means, the latter means being movable thereon to an accessible position, mechanism to provide relativescanning movement between said scanning device and said sheet supporting means, and means to provide for moving said sheet supporting means on its said carrying means to the accessible position independently of said mech-' anism whereby access may be had to said sheet.

28. Facsimile scanning mechanism comprising a rotatable drum to support a member to be scanned, a shaft extending axially through said drum to slidably and rotatably support the same, a member rigidly secured to and projecting from said shaft, and means in said drum to be engaged by said member to cause said drum to rotate with central station and. each terminating in a pair of I jacks available for connection to the apparatus in said central station, a volume control rheostat associated with one of said pair of jacks for each circuit, means whereby said central station apparatus is connected in series with said rheostat when connected to said communication circuit through said jack associated with said rheostat, said rheostat being omitted when said central station apparatus is connected to the communication circuit through the remaining jack.

25. In a telegraph system, a plurality of stations, a central station, communication circuits extending from said first named stations and terminating in said central station, simplexed connections at said central station for each of said communication circuits including a standby source ofpotential for said simplexed circuits, and means to disconnect said standby potential from said simplexed crcuits when the apparatus of said central station is connected to said communication circuits.

26. In a telegraph system, a plurality of stations, a central station, communication circuits extending from said first named stations to said central station and terminating at a point conveniently available for connection to the apparatus of said central station, a single jack forming the terminus of each communication circuit, transmitting apparatus and receiving apparatus in said central station, a plug associated with said transmitting apparatus, a second plug associated with said receiving apparatus, a calling signal and a transmission signal associated with each Jack, each jack affording communication from said transmitting apparatus or said receiving apparatus to the first named station associated therewith.

said shaft, said means permitting limited angular movement of said drum with respect to said shaft.

29. A facsimile telegraph system comprising means to generate currents representing the varying intensities of light and shadow of the transmitted subject matter, vacuum tube, means to apply signals represen to the input circuit of said vacuum tube, recording means for cooperating with a sensitive receiving surface, said'recording'means being connected to the output circuit of said vacuum tube, a source of current supply, means to furnish simultaneously current to said recording means a and space current for said vacuum tube, and means including a resistance for varying inversely the two currents derived from said source.

30. A facsimile telegraph systemcomprising means to generate currents representing the varying intensities of light and shadow of the transmitted subject matter, a vacuum tube,

'means to apply signals representing said currents to the input circuit of said vacuum tube, a recording circuit including an electrode and an electrosensitive receiving surface, a source of current supply, and means including a resistance for connecting said source in parallel with said recording circuit and the space discharge path of saidvacuum tube whereby the currents in the recording circuit and the space discharge path of the vacuum tube vary inversely when signals are I applied to the input circuit of said vacuum tube.

RALEIGH J. WISE.

G. STEWART. ROBERT D. PARROTT.

said currents 

